Theoretical interpretation of the line shape of the gaseous acetic acid cyclic dimer

A general quantum theoretical approach of the nu(X-H) IR line shape of cyclic dimers of weakly H-bonded species in the gas phase is proposed. In this model, the adiabatic approximation (allowing to separate the high frequency motion from the slow one of the H-bond bridge), is performed for each separate H-bond bridge of the dimer and a strong nonadiabatic correction is introduced into the model via the resonant exchange between the fast mode excited states of the two moieties. The present model reduces satisfactorily to many models in the literature dealing with more special situations. It has been applied to the cyclic dimers (CD(3)CO(2)H)(2) and (CD(3)CO(2)D)(2) in the gas phase. It correctly fits the experimental line shape of the hydrogenated compound and predict satisfactorily the evolution in the line shapes, to the deuterated one by reducing simply the angular frequency of the H-bond bridge and the anharmonic coupling parameter by the factor 1/ square root of 2.     

A neutron study of the magnetic ordering in a NpAs2 single crystal

A neutron diffraction study on a small NpAs₂ single crystal is reported. NpAs₂ orders at T_N = 52 K with a pure sine wave modulation propagating along a ≤100≥ direction of the tetragonal unit cell. The value of the wave vector is incommensurate with the lattice (k = ≤0.141,0,0≥) and is temperature independent down to T_IC = 18.5 K where a first-order transition towards a commensurate ferromagnetic state occurs. At all temperatures the magnetic moments are aligned along the c-axis with a value of (1.45±0.1)μ_B at T = 5 K.     

Interpretation of the low even configurations of neutral protactinium (Pa I)

A new analysis of the spectrum of neutral protactinium led to revise and to extend the earlier level list. The Slater-Condon method was used to interpret the low even group of configurations 5f ²6d7s ²+5f ²6d ²7s with a root mean square deviation of 134cm^?1 for 64 energy levels.     

Thermal Transition of Bimetallic Metal–Phenolic Networks to Biomass‐Derived Hierarchically Porous Nanofibers

The development and utilization of biomass resources could contribute to new materials for long‐term sustainable energy storage and environmental applications, reduce environmental impacts, and meet the urgent need for green and sustainable development strategies. Herein, a bimetallic metal–phenolic network (MPN) was applied to incorporate different metallic element species into cattle skin and fabricate collagen‐fiber‐derived complex oxide nanofibers using natural polyphenols (Myrica tannins). Direct thermal transition of these biomass–MPN composites generates hierarchically porous nanofibers possessing micro‐ and mesoporous architectures along with a well‐preserved macroscopic structure. The pore system and complex oxide composition provide excellent photocatalytic performance. This low‐cost, simple, and readily scalable MPN‐based approach provides a straightforward route to synthesize nanostructured materials directly from biomass, which could play important roles in a wide range of potential applications.     

Crystal chemistry,magnetic, and electrical properties of the tetragonal plutonium oxide telluride Pu2O2Te

We describe the preparation and some physical properties of Pu₂O₂Te. The plutonium oxide telluride is isostructural with the corresponding rare-earth oxide tellurides which crystallize in the tetragonal system of La₂O₂Te-type. Magnetic susceptibility data from 4 K to room temperature are reported together with resistivity measurements. Pu₂O₂Te is found to be an antiferromagnet below 56 K and a semiconductor with an intrinsic energy gap of 0.65 eV. The magnetic behavior is interpreted in terms of superexchange coupling interactions via nonmetal p orbitals, i.e., in terms of 5f-p overlaps. This conclusion is supported by crystal chemistry considerations by comparison of cell volumes of Pu₂O₂Te and Nd₂O₂Te. In Pu₂O₂Te, the Pu crystal radius is found to be much lower than that of Nd in Nd₂O₂Te, suggesting some 5f electron “delocalization” leading to a crystal radius shrinkage. As for the hexagonal Pu₂O₂X compounds, with X = O, S, Se, the measured gap may be considered as the energy separation between the chalcogen np band and the 6d-7s conduction band, the occupied 5f states lying just below the np band with some 5f-np overlap.     

In-silico guided discovery of novel CCR9 antagonists

Antagonism of CCR9 is a promising mechanism for treatment of inflammatory bowel disease, including ulcerative colitis and Crohn’s disease. There is limited experimental data on CCR9 and its ligands, complicating efforts to identify new small molecule antagonists. We present here results of a successful virtual screening and rational hit-to-lead campaign that led to the discovery and initial optimization of novel CCR9 antagonists. This work uses a novel data fusion strategy to integrate the output of multiple computational tools, such as 2D similarity search, shape similarity, pharmacophore searching, and molecular docking, as well as the identification and incorporation of privileged chemokine fragments. The application of various ranking strategies, which combined consensus and parallel selection methods to achieve a balance of enrichment and novelty, resulted in 198 virtual screening hits in total, with an overall hit rate of 18%. Several hits were developed into early leads through targeted synthesis and purchase of analogs.     

Extended diffusion in a double well potential: Transition from classical to quantum regime

The transition between the classical and quantum regimes in the diffusion of a particle in a 2-4 double-well potential is treated via the strong collision model in the high-temperature limit. Both the classical and semiclassical position correlation functions, their spectra, and correlation times are evaluated using the memory function formalism. It is shown that even in the high temperature limit, marked classical-quantum transition effects appear in the observables when collisions are rare.     

Photodynamic therapy can improve warts' discomfort in renal transplant patients prospective multicenter study

Many studies have been conducted showing that aminolevulinic acid (ALA)-photodynamic therapy (PDT) can be an alternative treatment for recalcitrant warts. Recently, we performed a study evaluating methyl-aminolevulinic acid (MAL)-PDT for the treatment of hand warts in a population of renal transplant patients. Two symmetrical targets were selected on each hand and randomly assigned to chemical keratolytic treatment followed by three cycles of ALA-PDT (75 J cm(-2) red light). Patients were evaluated after 3 months and a second run of PDT was performed if the total area and number of warts decreased less than 50%, with evaluation every 3 months for 1 year. Twenty patients were included and 16 were evaluable (9 M, 7 F). After 6 months the reduction of warts' area was 48.4% on the treated side versus 18.4% in the control area (P = 0.021). The decrease in the total number of warts was 41%versus 19.4% (P = NS). The global tolerance of the treatment was good with acceptable pain during irradiation. These results suggest that ALA-PDT is a safe and efficient treatment for transplanted patient warts. The improvement between treated and control zone is 20% due to the decrease in untreated warts' area and number.     

Preparation of tetrazoles from organic nitriles and sodium azide in micellar media

An effective method for the preparation of 5-substituted tetrazoles from the corresponding nitriles in micellar media is described. It was demonstrated that almost quantitative yields of tetrazoles can be obtained if the amount of water-surfactant is optimized. The advantages of the methods presented over many others currently used are the simplicity, facility of isolation of tetrazole products and elimination of using relatively expensive solvents and reagents.